1. Field of the Invention
The present invention relates to a control device for an article wherein flavor-generating materials are heated to release tobacco flavors. More particularly, it relates to a device adapted to initiate heating of the flavor-generating material.
2. Description of Related Art
Flavor-generating articles generally are known in the art. In such articles, flavor beds of tobacco or tobacco-derived material are heated to release tobacco flavors without producing all the normal products of tobacco combustion. In some such devices, a combustible heat source is used to heat air which is then drawn past a bed of flavor-generating material to heat the material and thereby release the tobacco flavor. In other such devices, the flavor-generating material is heated electrically.
In the above-described devices, the user initiates heating of the flavor-generating material by drawing air into his mouth. In the case of the combustible heat source device, the air is drawn through or around the heat source and then past a bed of flavor-generating material to heat the material. For the electrical heat source device, the user's draw is detected by a pressure or air flow sensor, which in turn initiates heating of the flavor-generating material.
In the flavor generators described above, there occurs between the start of the draw and the release of flavor from the flavor-generating material a substantial lapse of time, as compared to that which occurs in conventional cigarettes. Users find this lag time to be a negative attribute of such flavor generators. Another problem with current flavor generators is that some users do not draw air for a long enough period of time to permit full release of the flavor materials before the draw is complete. Again, this deficiency in current flavor generators can result in user dissatisfaction.
In electrical flavor generators in particular, various non-draw activities can create an air flow or pressure change within the device to falsely or prematurely initiate the heating sequence. For example, if the user waves the article in his hands or otherwise agitates the device, the heating mechanism may be falsely triggered. Also, if the user talks while holding the article between his lips, the heating mechanism may be falsely or prematurely triggered.
These problems can be avoided by using an entirely different mechanism to control the heating sequence. One proposed mechanism involves the use of a push button device which the user must activate for each draw. This mechanism is itself unattractive, however, because it requires user action substantially different than that practiced by smokers of conventional cigarettes.
Accordingly, it is an object of the present invention to provide a control device for a flavor-generating article that initiates heating of flavor-generating material such that there is only a small lapse of time between the start of the user's draw and the delivery of flavor to the user.
It is also an object of this invention to provide a control device that is resistant to false non-draw air flow or pressure changes.
It is a further object of this invention to provide a control device that responds to the user's normal smoking behavior to initiate heating of the flavor-generating material.